Thank you for your reply
It's a sticky thing, as I arrived home I watched once more the bottom of my favourite board and the bursts were getting flatter, most of them disappeared

But a few of them are present, especially where the paint is very thin (the original color of the wood is to be seen).
I hate this "limited finish". With a normal thickness painting it would be perfect and less vulnerable.
2 more questions and I don't disturb you with that problem
1. What dou you think about the real value of this limited painting? I mean this is simply marketing, not a pregnant weight save (but cost save surely...)
2. How does affect the flaking off of the painting the water impermeability? (should I always repair?)
Thanks once more